Abstract
Classical organometallic reagents such as alkyl-lithium and magnesium compounds as well as a large number of lithiated species which are substituted by resonance-stabilizing groups or hetero-atoms can be convened into the titanium analogs using cheap quenching reagents. This increases
chemoselectivity dramatically and also has a profound influence on stereoseleetivity in reactions with carbonyl compounds. Since the nature of the ligands at titanium can ge varied systematically, it is possible to control the electronic and steric environment at the metal in a predictable manner. Besides increasing selectivity, several novel reaction types are possible.
